How to change the bit field of a property in a class from another class

SystemVerilog
,
1

Let us say there are two classes a1, b1 extending from different parent classes.
How to set the “change_value” field in class a1 from class b1

class a1 extends random_class;
bit[change_value -1:0] data;
..
..
endclass

class b1 extends check_class;
//what to do in class b1 to set the "change_value" in class a1
..
..

endclass

Please help in this context

2

In reply to Prashanthp436:

There is no solution to the question you have asked. It would help to explain how you think change_value would be declared even without class b1 involved, and what it is you expect to be able to accomplish with this feature. Otherwise this is an XY problem.